| 摘要 |
<p>A filter media having an increased efficiency is provided. The filter media includes a middle filtering layer formed from at least one meltblown layer and having a dust entering side and a dust exiting side. A first outer layer is disposed on the dust entering side of the filter media and is formed from a meltblown polymer fiber web, and a second outer supporting layer, or backing, is disposed on the dust exiting side of the filter media, and is formed from a spunbond polymer fiber web. In an exemplary embodiment, the middle filtering layer includes a first, upstream meltblown layer and a second, downstream meltblown layer. The first, upstream layer is preferably formed from fibers having a diameter greater than a diameter of the fibers forming the second, downstream layer. The filter media is particularly useful to form ASHRAE filters for applications including heating, refrigeration, and air conditioning filtration.</p> |
